Many key cellular interactions involve mechanotransduction (MT), whereby forces applied by other cells or by the matrix lead to biochemical and morphological sequellae. Since MT may be a useful target of molecular therapies, I have developed a rapid assay for it: the flow cytomechanical assay (FCMA). The assay exposes suspended cells to graded hydrostatic challenges prior to their entry into a standard flow cytometer. Preliminary results on 7 cell types have shown that FCMA can measure key aspects of MT at a rate of 10,000 cells per minute. FCMA could be a useful screening tool for agents and materials that involve MT.